1.Field of the Invention
The present invention generally relates to voltage supply interfaces. More specifically, the present invention provides a voltage supply interface having more accurate control and reduced series resistance.
2. Background Art
A voltage supply interface provides voltage and current to a next stage circuit device from a primary voltage supply. The voltage supply interface uses a switch to slowly power on the next stage circuit device when the next state circuit device is coupled to the primary voltage supply.
The voltage supply interface monitors the current supplied to the next stage circuit device to control the power supplied to the next stage circuit device. A conventional voltage supply interface uses a sense resistor that is in series with the next stage device to monitor the current. The sense resistor is required to be large to provide accurate current monitoring. A resulting large voltage drop across the sense resistor, however, reduces the power supplied to the next stage device. Further, supplying an adjustable current is difficult with the use of a single, inflexible switch.
Therefore, there exists a need for a voltage supply interface that provides more accurate control of the current supplied to the next stage device that minimizes or eliminates the power loss from the required sense resistor.